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mysqlperformanceinnodbsql-deletelarge-data

The best way to delete 5K rows from Innodb table with 30M rows


table:

  • foreign_id_1
  • foreign_id_2
  • integer
  • date1
  • date2
  • primary(foreign_id_1, foreign_id_2)

Query: delete from table where (foreign_id_1 = ? or foreign_id_2 = ?) and date2 < ?

Without date query takes about 40 sec. That's too high :( With date much more longer..

The options are:

  • create another table and insert select, then rename
  • use limit and run query multiple times
  • split query to run for foreign_id_1 then foreign_id_2
  • use select then delete by single row

Is there any faster way?


mysql> explain select * from compatibility where user_id = 193 or person_id = 193 \G
           id: 1
  select_type: SIMPLE
        table: compatibility
         type: index_merge
possible_keys: PRIMARY,compatibility_person_id_user_id
          key: PRIMARY,compatibility_person_id_user_id
      key_len: 4,4
          ref: NULL
         rows: 2
        Extra: Using union(PRIMARY,compatibility_person_id_user_id); Using where
1 row in set (0.00 sec)

mysql> explain select * from compatibility where (user_id = 193 or person_id = 193) and updated_at < '2010-12-02 22:55:33' \G
*************************** 1. row ***************************
           id: 1
  select_type: SIMPLE
        table: compatibility
         type: index_merge
possible_keys: PRIMARY,compatibility_person_id_user_id
          key: PRIMARY,compatibility_person_id_user_id
      key_len: 4,4
          ref: NULL
         rows: 2
        Extra: Using union(PRIMARY,compatibility_person_id_user_id); Using where
1 row in set (0.00 sec)

Solution

  • By now data amount is 40M (+33%) and rapidly growing. So I've started looking for other, some no-sql, solution.

    Thanks.